Study 1 Raw Data from Early life manipulations of vasopressin-family peptides alter vocal learning

Vocal learning from social partners is crucial for the successful development of communication in a wide range of species. Social interactions organize attention and enhance motivation to learn species-typical behaviour. However, the neurobiological mechanisms connecting social motivation and vocal learning are unknown. Using zebra finches (Taeniopygia guttata), a ubiquitous model for vocal learning, we show that manipulations of non-apeptide hormones in the vasopressin family (arginine vasotocin (AVT)) early in development can promote or disrupt both song and social motivation. Young male zebra finches, like human infants, are socially gregarious and require interactive feedback from adult tutors to learn mature vocal forms. To investigate the role of social motivational mechanisms in song learning, in two studies, we injected hatchling males with AVT or Manning compound (MC, a non-apeptide receptor antagonist) on days 2–8 post-hatching and recorded song at maturity. In both studies, MC males produced a worse match to tutor song than controls. In Study 2, which experimentally controlled for tutor and genetic factors, AVT males also learned song significantly better compared with controls. Furthermore, song similarity correlated with several measures of social motivation throughout development. These findings provide the first evidence that non-apeptides are critical to the development of vocal learning.

从社交伙伴处习得鸣唱，对于众多物种的通信功能顺利发育至关重要。社交互动可调控注意力并提升个体学习物种典型行为的动机，但联结社交动机与鸣唱学习的神经生物学机制仍未明晰。本研究以鸣唱学习研究的经典模式生物——斑胸草雀（Taeniopygia guttata）为实验对象，证实发育早期对血管加压素家族非肽类激素（精氨酸加压素（AVT））进行干预，可双向调控鸣唱与社交动机，既能促进也能损害其发育。与人类婴儿类似，幼年雄性斑胸草雀具有社交群居性，且需要成年导师的互动反馈才能习得成熟的鸣唱模式。为探究社交动机机制在鸣唱学习中的作用，本研究开展两项实验：在孵化后第2至8天，向刚孵化的雄性幼雀注射AVT或曼宁化合物（MC，一种非肽类受体拮抗剂），并在其成年后记录鸣唱行为。两项实验均显示，MC处理组幼雀成年后的鸣唱与导师鸣唱的匹配度显著低于对照组。在第二项实验中，研究者通过实验设计控制了导师与遗传因素的干扰，结果显示AVT处理组幼雀的鸣唱学习效果同样显著优于对照组。此外，鸣唱相似度与发育过程中多项社交动机相关指标存在显著相关性。本研究结果首次证实，非肽类激素对于鸣唱学习的发育具有关键作用。